anyone who knows about growing muscle..help!

Hey guys, I’m 5’3 & a half & weigh about 135 right now. I don’t really consider myself fat, but I hate my legs and my butt. My thighs have stretch marks and cellulite along with my butt. My intentions aren’t to lose weight, but to turn this weight into muscle! I have a gym membership at planet fitness and would like to work on my lower body, but I’m not sure how. How many times a week should I squat and do lower body exercises, what should I eat to make this happen, what exercises should I do to grow these muscles? Any advice y’all could give me (even anything I didn’t ask) would be awesome!!